Quantity indicating device for liquids



June 28, 1932.

J. MACCALLUM. JR

QUANTITY INDICATING DEVICE FOR LIQUIDS Filed Sept. 25, 1922 2 Sheets-Sheet l N /f q /a June 28, 1932. MAccALLUM JR 1,865,263

QUANTITY INDICATING DEVICE FOR LIQUIDS Filed Sept. 25, 1922 2 Sheets-Sheet 2 Patented June 28, 1%32 JAMES MACG'ALLUM, JR., OF ST. LOUIS, MISSOURI QUANTITY INDICATING DEVICE FOR LIQUIDS Application filed. September 25, 1922.

My invention relates to improvements in quantity indicating devices for liquids, and has for its object a means for automatically delivering a pressure carrying medium or t gas to the pressure chamber of an indicating device.

A further object is to construct a pressure indicating device which is equipped; with means operated by the surge, splash, or bodily movement of the liquid within a liquid container, or by movement of the container itself or the vehicle carrying the container to supply a pressure carrying medium or gas beneath the pressure chamber of an indicating ii device.

In the drawings,

Fig. 1 is a side elevation of a pressure indi cating device, showing the same in position within the tank, with parts broken away and w: in section.

Fig. 2 is a section taken on the line 22 of Fig. 1.

Fig. 3 is a vertical cross section of a modified form of a pump, in which the surge of liquid within the container is used as the motive power for operating the pump.

Fig. i is a cross section of a modified'form of pump chamber.

Fig. 5 is a longitudinal section of the same.

Fig. 6 is a tragmental section of the liquid container, showing a plunger pump secured therein, said pump being operated by the surge or splash of the liquid within the container.

Iifi F 7 is a modified view, showing a structure whereby the surge of the liquid causes the liquid to pass through a tunnel, and thereby draws a pressure carrying medium downward.

W 7a is a sectional view of a modified form wherein the diaphragm is operated by the pulsations of either the intake or exhaust gases.

Fi 8 is another modi lied form wherein the speed oi the vehicle is utilized to deliver air beneath the pre ure chamber.

Fig. 9 is VTtlCtl section of a pump which is operated by the joltin of vehicle.

Fig. 10 is a modified form of a pump in which the air above the liquid is exhausted Serial No. 550,302.

and driven from the container, and fresh air to take its place drawn downward and delivered beneath the pressure chamber.

Fig. 11 is a modified form wherein the expansion of air is used-the air being heated 65 by being located in a container which contacts with the hottest part of an internal combustion engine, or exhaust and mutller.

Fig. 12 is a modified form of plunger pump wherein the same is operated by the move- 80 ment or" the supporting springs of the vehicle.

in the construction of my device I employ a liquid container 13. This liquid container is preferably provided with a flange 14: which surrounds an opening 15 formed in the top of the container. This flange is screw-threaded and has placed thereon a disc 16 which is secured to the flange by means of a collar 17. The disc or plate 16 is provided with a tapered screw-threaded opening 18, in which a tapered split nut 19 is seated. Passing through this nut is a pipe 20. This pipe is adapted to be held by screwing down the nut 19, which, due to the split tapered construc tion, clamps the pipe and holds it against movement. The pipe 20 is provided with a reduced portion 21 which is connected to an indicating gage 22. This indicating gage may be of any desired construction, and is preferably of the pressure indicating type. The lower end 23 of the pipe 20 is cut away and secured within a pressure chamber 24. This pressure chamber has a concave bottom 25 which is provided with openings 26. Surrounding the lower portion of the chamber 24 is a cup 27 which is provided with outwardly extending ducts or passages 28. thus permitting liquid to pass therethrough and underneath the pressure chamber,through one of these ducts extends a pipe 29, its lower end 30 extending beneath the pressure chamber. The pipe 29 extends upward to a point near or at the top of the container. It is then bent and extends downward, and has its end 31 secured to the valve chamber 32 of a diaphragm pump 33. This diaphragm pump is preferably of the double-diaphragm type, as illustrated, although a single diaphragn'i may be used by using a rigid member instead of one 0-1 the flexible walls. Secured to the pump 33 is a duct or passageway 3% which is secured to the plate or disc 16, and extends therethrough, terminating flush with the upper surface. 35 indicates a valve which is unseated inwardly so that the line or duct 34 will act as a suction line, while the valve 36 unseats outwardly and allows pressure from the pump to pass into the pipe 29, and be delivered beneath the pressure chamber. In this device the upward and downward movement of the container and the inertia of the liquid causes the liquid to press on the diaphragms of the pump, and cause them to partially collapse. This action unseats the valve 36 and forces air into the pipe 29. The diaphragm is normally tensioned as shown in the drawings, which prevents the outward movement of one diaphragm when the other is collapsed and as soon as pressure on the diaphragm is released it again assumes the position shown in Fig. 1. This causes a suction to be set up within the pump, and seats the valve 36. The suction thus set up then unseats the valve 35 and draws air or gas through the pipe 3 1 into the pump chamber to take the place of the air previously driven into the pipe 29. In this way there will always be a certain amount of air or gas delivered beneath the pressure chamber 2% as long as the vehicle is in motion, and consequently the pressure chamber 24 will be constantly supplied with additional pressure carrying medium, and obviate any inaccuracy in indication, due to loss of volume of the pressure carrying medium within the pressure chamher, and the line leading therefrom to the indicating gage.

In Fig. 3 I have shown a diaphragm pump 37 which is provided with diaphragms 38 and 39, and with a pressure receiving line 10 and suction line 41. In this construction the pump instead of being pl. ced horizontally as illustrated in Figs. 1 and 2, is placed in a vertical position as shown, so that any surge or sidewise movement of the liquid within the container will act alternately on the diaphragms 38 and 39, and create a pump action the diaphragms being normally at the outer limit of their expansion. It is to be understood that the pipe 40 has the same shape as the pipe 29 and terminates below the pressure chamber where it is immersed in the liquid. This liquid acts as a seal and prevents the air from passing back into the pump.

I may if desired eliminate the valves 35 and 36, for the reason that the suction pipe is smaller than the delivery or pressure pipe, and will not allow air to pass as readily therethrough. In this way, while the pump may not be quite so effective as the style of pump shown in Fig. 1, still a sufiicient amount of air will be forced down to the underside of the pressure chamber to keep the device to the highest point of efiiciency.

In Figs. 4 and 5 I have shown a modified construction of pump chamber in which a tube of very thin resilient material is used as the pump, and takes the place of a diaphragm. In this construction a length of tube is first taken and partially flattened, so as to be substantially elliptical. The open ends of the pipe are then pressed together and soldered, so as to form an air tight chamber. This construction will act exactly the same as the diaphragm pump.

In Fig. 6, 42 indicates a liquid container. To the top of this liquid container is secured a pump chamber 43 which communicates with the atmosphere or with a gas container by means of a passage 4%. The side wall of the pump is provided with an opening 45, surrounding which is a valve chamber 46 in which a ball valve 47 is located. The ball of the valve is held against too great a movement by means of a screw 48. Connected to the valve chamber 46 is a nipple 49 to which a pressure line 50 is connected. This pressure line terminates beneath the pressure chamber of the indicating device in the same manner as illustrated in Fig. 1. Located within the pump chamber is a piston 51 which has a piston rod 52. This piston rod is provided with a pin 53 which fits into the slot 5& formed in the arm 55 of a bell crank lever. The arm 56 of this bell crank lever depends downwardly and is secured to a plate 57, which plate is acted 011 by the side-wash or surge of the liquid, and when either in or above the liquid swings under the influence of body movement imparted thereto and by the influence of gravity. In other words this paddle operates on the same principle as a pendulum swinging to and fro, and this in turn operates the plunger or piston 51, pumping air or gas through the pressure line 50, and delivering it beneath the pressure chamber. The bell crank lever is supported by means of a bracket 58 which is attached to any convenient place in the container.

In Fig. 7 I have shown a method of drawing the pressure carrying medium to a point beneath the pressure chamber. In this figure, 59 represents the liquid container, 60 the pressure chamber, 61 the pressure line leading to the indicating gage, and 62 is the bottom of the pressure chamber. The pressure chamher is preferably supported on legs 63, so that the liquid will have free passage thereunder. Located adjacent the bottom of the tank is a funnel 64 which terminates in a pipe 65. The open end 66 of this pipe terminates beneath the pressnre chamber 60. Secured to the pipe is a branch pipe 67 which extends upward through the top of the container.

In the operation of this device, the liquid when surging or side-washing, enters the funnel 64, and is driven through the pipe 65 and out through the open end 66 at a relatively high rate of speed. This rapid action of the liquid draws down air or gas through the pipe 67 after the manner of an injector, and carries this air with it beneath the pressure chamber 60. As soon as this air passes out from the end 66, it rises and lodges beneath the bottom 62 from where it passes through suitable openings into the pressure chamher.

In Fig. 8 I have shown a device which has an enlargement 68 which terminates in a pipe 69. This pipe preferably terminates in a container 70 which is partially filled with liquid so that the bottom of the pipe 69 is submerged. The container is filled through the opening 71, and for cleaning purposes the bottom 72 can be removed. Within the top of the container 70 is located a pressure line 73. The remainder of the construction of the pipe 73 the st ne as previously described, that is, terminating beneath the pressure chamber or the pipe 69 may terminate beneath the pressure chamber and the remainder omitted. This device is preferably placed close to the radiator of an automobile,

and receives not only the air which passes through the radiator due to the speed of the machine, but also the increased speed of the air due to the action of the fan. The air thus received will contain dust and impurities, and it is for this reason that I make use of the container 70 which purifies or washes the air before it is delivered into the liquid container through the pipe 73. Were this air not cleansed in some way, it would only be a short time before the fuel line leading from the container to the carburetor of an engine would become clogged up.

In Fig. 9, 81 represents a pump having a piston 82, and a piston rod 83, which projects through the head 84 of the pump. Secured to the projecting end of the piston rod 83 is a weight 85, and between the weight and head 84 is interposed a coil spring 86. The pump is also provided with suction valves 87, and a discharge valve 88, and surround ing this discharge valve is a pressure line 89. This device is intended to be attached at any convenient point without the container, so that any up and down movement will cause the weight 85 and spring 86 to alternately act on the piston 82, thereby continuously pumping air beneath the pressure chamber as long as the vehicle is in motion.

In Fig. 10 I have shown another modified form wherein the container is preferably closed against the admission of air. In other words, no vent provided in the filler cap. In this device the container 7-1 is provided with a pump 75. The suction line 76 terminating at the upper end of the container, while the pressure line 77 communicates with the. outside atmosphere. In this device an air line 78 having its upper end opening through the top of the container and its lower end 79 terminating beneath the pressure chamber 80 is employed. As the pump 75 is acted on by the movement of the liquid it exhausts air from above the liquid and pumps it out through the pipe 77. A partial vacuum is now set up in the tank. This partial vacuum draws air downward through the pipe 78 and allows it to flow out through the end 7 9, where it lodges beneath the pressure chamber 80.. After a short time the entire underside of the bottom will hecome filled with air, and any additional air delivered by the pipe 78 will pass on and up through the liquid to be again pumped out by the pump 75. In this way a constant stream of air or gas is drawn downward and delivered beneath the air pressure chamber.

In Fig. 11 I have shown a modified form in which air located within a container 90 is heated by having the container in contact with the hottest point of an internal combustion engine. In the present drawing it is shown as coiled around the exhaust pipe 91. I do not desire, however, to limit myself to this precise form of container, or its location, as I may find other points in the engine which heat more qu'clrly and to a higher degree, than the exhaust pipe. The container or compartment 90 has connected thereto a pressure carrying line 92, and also a valve chamber 93, the line 92 terminating beneath the air pressure chamber of the indicating device, where it is sealed by the liquid within the container. The valve chamber 93 acts as a check valve when the air is heated, and causes it to be expelled through the liquid and beneath the container, but when the air cools, the valve is sensitive enough to be unseated, and allows additional air to be drawn in, so that there. will be no possibility of drawing liquid through the pipe 92 into the expansion compartment 90.

In Fig. 12 I have shown still another modified form of construction in which 9% represents the chassis of a vehicle, and 95 the suspension spring. To the chassis is secured a pump 96 having an inlet 97 and an outlet 98. A piston rod 99 projects from this pump which terminates in a plate 100. Secured to the plate 100 is a spring 101 which contacts with the vehicle spring 95, and surrounding the piston rod 99 is a coil spring 102. This coil spring normally tends to force the plate 100 away from the pump casing. The purpose of the spring 101 is to prevent injury to the pump due to any excessive or severe road shocks. he spring 101 is stiffer than the spring 102, so that it will at all times actuate the pump, but is not suiiiciently stiff to cause the pistion rod 99 to be bent when a severe shock is imparted, as the spring 101 will then compress and prevent any injury to the pump.

I'Vhile- I have shown the Jump in Fig. 12 as being attached to the chassis in contact with the spring, still is obvious that the pump can be attached at various points on modified form of pump in which 103 repre-,

sents either the intake or exhaust manifold pipe. his pipe is provided with a nipple lot over which a cap 105 is screwed, and between the cap and nipple is secured a diaphragm 108. The cap 105 acts as a pump chamber having a suction line 107, and a pressure line 108. This pump is worked by the pulations of the gases either entering or passing from the engine. By reversing the valve action on this pump the same instead of supplying pressure can be used to create a vacuum.

It is also to be understood that in all the devices. any style of pump may be used, instead of the specific type shown and that the liquid communicating between the tank and the pump will surge as the pump operates.

he only cc ion to this being Figs. '4', 8 and ll. in winch no pump is used.

Having fully described my invention, what I claim is:

1. In a quantity indicating device for liquid containers a pressure chamber having an opening in its bottom located in said container at the full depth to be measured, a pressure indicating gauge, a pipe connecting said pressure chamber and gauge, a duct having one end terminating below the pressure J chamber, and pumping means located in the container and securedto the opposite end of said duct, said pumping means adapted to be operated by the surge of the liquid in the container for forcing a gaseous pressure carrying medium through said duct and delivering it beneath the pressure chamber.

2. A quantity indicating device for liquids comprising in combination with a pressure chamber submerged in and communicating at its bottom with a liquid at the full depth to be measured, a pressure responsive indicating gauge, a line connecting said chamber and gauge, a duct terminating beneath said pressure chamber. air pumping means located within said container and secured to the opposite end of said duct. said pumping means adopted to be operated by the bodily movement of the liquid in said container for "forcmg a pressure carrying medium through said duct and discharging it beneath the pressure chamber, and means for preventing said t charged pressure carrying medium from r. entering said duct.

3. In a quantity indicating device for liquid containers, a pressure responsive gauge, a liquid container, a pressure chamber having a perforate bottom located in said container at the full depth to be measured. a pipe connection between the pressure chamber and gauge, a conduit having one end located beneath the bottom of the pressure chamber, and a pump located in said container and secured to the other end of said conduit, said pump being provided with means adapted to be operated by the movement of the liquid in the container for operating said pump for drawing in and forcing a pressure carrying medium through said conduit and delivering the same beneath the bottom of said pressure chamber.

4. In a quantity indicating device for liquid containers, a pressure responsive gauge, a liquid container, a pressure chamber lo cated in said container and communicating at its bottom with the liquid at the full depth to be measured, a hollow connection between said pressure chamber and gauge, a conduit adjacent said pressure chamber and having one end terminating beneath the pressure chamber, air pumping means located within the container and secured to the opposite end of said conduit, means secured to said pump and adapted to be operated by the movement of the liquid within the container when the same is moved for placing said pump in operation thereby forcing air through said conduit and beneath the pressure chamber, and means for preventing the air beneath said pressure chamber from being carried away by the surge of the liquid.

5. The combination with a tank for a motor vehicle and to contain a supply of liquid fuel therefor, of a pressure responsive gage to be mounted on the vehicle, an air conduit connected with the gage and extending down into the liquid in the tank and open to the same adjacent the bottom of the tank, said conduit serving to confine a column of air between the gage and the liquid at the lower end of the conduit for operating the gage by the hydrostatic head of the liquid in the tank acting against said air column for indicating the amount of liquid in the tank, an air pump supported in the tank, an air pipe connecting the pump with the conduit for replenishing the supply of air thereto in the operation '5 the pump, and means in the tank and moved by the wash of the liquid therein and connected with the pump for operating the same.

6. The combination with a tank for a motor vehicle and to contain a supply of liquid fuel therefor, of a pressure responsive gage to be mounted on the vehicle, an air conduit connected with the gage and extending down into the liquid in the tank and open to the same adjacent the bottom of the tank, said conduit serving to confine a column of air between the gage and the liquid at the lower end of the conduit for operating the gage by the hydrostatic head of the liquid in the tank acting against said air column for indicating the amount of liquid in the tank, an air pump supported in the tank, an air pipe connecting the pump with the conduit for replenishing the supply of air thereto in the operation of the pump, a paddle pivotally supported in the tank and disposed to be moved back and forth by the wash of the liquid therein, and means connecting the paddle with the pump for operating the same.

7. A liquid level gauge for indicating the height of the liquid level in a storage tank intended to be subjected to movement, comprising an indicating device responsive to fluid pressure, a conduit having one end extending to the lower part of the storage tank and open to the liquid therein and its other end communicating with said indicating device, and a pump having an outlet communicating with the conduit and an air inlet opening above the liquid, said pump having an actuating member responsive to the surge of the liquid in the tank, the pump being operated by said member for producing and maintaining fluid pressure in said conduit.

8. Adevice for indicating the quantity of liquid in a reservoir including an air-containin g pressure-transmitting chamber immersed in and communicating with the liquid in the reservoir, an external pressure-responsive indicator having an air connection to the chamber, and a reciprocating inertia air pump adapted to be operated by bodily movement imparted to the pump so as to force air into said chamber to replenish the air supply therein.

9. A device for indicating the quantity of liquid in a reservoir including in combination an air-containing pressure-trans1nitting chamber immersed in and communicating with the liquid in the reservoir, an external pressure-responsive indicator having an air connection to the chamber and inertia means adapted to be actuated by the motion of a vehicle on which the tank may be mounted for replenishing the loss of air from said cham ber.

10. A device for indicating the quantity of liquid in a reservoir including an air containing pressure transmitting chamber immersed in and communicating with the liquid in the reservoir, an external pressure responsive indicator having an air connection with the chamber, and pumping means connected between said chamber and the atmosphere and operated by the bodily movement of a vehicle carrying said reservoir for replenishing the loss of air within said air containing pressure transmitting chamber.

11. A device for indicating the quantity of liquid in a container including in combination an air containing pressure transmitting chamber immersed in and communicating with the liquid in the container, a pressure responsive indicator, a conduit connecting said pressure responsive indicator and pressure transmitting chamber, a pump having a pressure responsive wall and located in said container and adapted to be operated by the inertia of the liquid in the container when said container is bodily moved, and a conduit communicating with said pump and pressure transmitting chamber.

12. A device for indicating the quantity of liquid in a container including in combination an air containing pressure transmitting chamber immersed in the liquid whose quantity is to be determined and adapted to have pressure created therein by the head of the liquid in said container, a pressure responsive indicator, a conduit connecting said pressure responsive indicator and the pressure transmitting chamber, a pump having pressure responsive walls located in said container and adapted to be operated by the inertia of the liquid in said container when the same is bodily moved, and a conduit connecting said pump with said pressure transmitting chamber.

13. A device for indicating the quantity of liquid in a container in combination with an air containing pressure transmitting chamber immersed in and communicating with the liquid in said container at the full depth to be measured, a pressure responsive indicator, a conduit connecting said chamber and indicator, pumping means havinga pressure responsive wall located within said container, said wall adapted to be operated by the inertia of the liquid in the container when said container is bodily moved, and a conduit communicating with said pumping means and said chamber whereby air is supplied to said chamber when the container is moved.

14. The combination with a tank for a motor vehicle and to contain a supply of liquid fuel therefor, of a pressure responsive gage to be mounted on the vehicle, an inverted cup at the bottom of the tank and open at its lower end to the liquid therein, an air conduit connecting the top of the cup with the gage, said conduct confining a column of air between the gage and the liquid in the cup for operating the gage by the hydrostatic head of the liquid in the tank acting against said air column for indicating the amount of liquid in the tank, an air pump supported in the tank and having an air intake above the maximum level of the liquid in the tank, an air pipe connected with the pump discharge and opening into the cup below the level of the liquid therein for replenishing the supply of air to the conduit through said cup in the operation of the pump, a paddle pivotally supported in the tank and disposed to be moved back and forth by the wash of the liquid therein, and means connecting the paddle with the pump for operating the same.

15. The combination with a tank for a motor vehicle to contain a supply of liquid fuel therefor, of a pressure responsive gage to be mounted on the vehicle, an air conduit connected with the gage and extending down into the liquid in the tank and open to the same, said conduit serving to confine a column of air between the gage and the liquid at the lower end of the conduit for operating the gage by the hydrostatic head of the liquid in the tank acting against said air column for indicating the amount of liquid in the tank, a pump in said tank and having a valvecontrolled air passage therefrom, a pipe connected to said air passage and containing a column of liquid surged up and down in the operation of the pump to force air from said pipe and into said conduit, and means in the tank and moved by the wash of the liquid therein and connected with the pump for opcrating the same.

16. The combination with a tank for a motor vehicle to contain a supply of liquid fuel therefor, of a pressure responsive gage to be mounted on the vehicle, an inverted cup at the bottom of the tank, an air conduit connecting the gage with said cup and serving to confine a column of air between the two, a cylinder supported in the tank, a reciprocating plunger extending into said cylinder from one end and being movable therein so that fluid may enter the cylinder from said tank through said end, means on said pump for controlling the discharge of air therefrom, an air pipe connecting said last-mentioned means with said cup, a paddle pivotally supported in the tank and disposed to be moved back and forth by the wash of the liquid therein, and means connecting the paddle with the plunger for operating the same.

17. The combinaton with a tank for a motor vehicle to contain a supply of liquid fuel therefor, of a pressure responsive gage to be mounted on the vehicle, an air conduit connected with the gage and extending down into the liquid in the tank and open to the same adjacent the bottom of the tank, said conduit serving to confine a column of air between the gage and liquid at the lower end of the conduit for operating the gage by the hydrostatic head of the liquid in the tank acting against said air column for indicating the amount of liquid in the tank, an air pumping mechanism and an operating paddle therefor located in the tank, and means connecting said pump with said conduit for replenishing the supply of air thereto in the operation of the pump, said tank having an opening in its top wall, a bracket arm supported by the tank and carrying said paddle, and means for supporting the arm in said tank.

18. A liquid level gauge for indicating the height of the liquid level in a storage tank intended to be subjected to movement, compris ing an indicating device responsive to fluid pressure, a conduit having one end extending to the lower part of the storage tank and open to the liquid therein and the other end of the conduit communicating with the indicating device, and means constructed to be actuated pressure, a conduit having one end extending I to the lower part of the storage tank and open to the liquid therein and the other end of the conduit communicating with the indicating device, and means constructed to be actuated by the surge of the liquid in the tank for producing and maintaining fluid pressure in the conduit, comprising a cylinder having a check valved outlet communicating with the conduit, a piston reciprocative in the cylinder and having an inlet for establishing communication between the space above the liquid in the tank and the pump cylinder below the piston, a pivoted paddle adapted to be oscillated by the surge of the liquid in the tank, and means operatively connecting the paddle with the piston to reciprocate said piston.

20. A liquid level gauge for indicating the height of the liquid level in a storage tank intended to be subjected to movement, comprising an indicating device responsive to fluid pressure, a. conduit having one end enlarged to form a chamber which extends to the lower part of the storage tank and is provided with vents which are open to the liquid in the tank and the other end of the conduit communicating with said indicating device,

a positively actuated pump having an actuating member responsive to the surge of the liquid in the tank, the pump being actuated by said member for producing and maintain-- ing fluid pressure in said conduit, said pump having an outlet communicating with the conduit and an air inlet opening above the liquid in the tank.

21. A liquid level gauge for indicating the height of the liquid in a storage tank intended to be subjected to movement, comprising an indicating device responsive to fluid pressure, a conduit having one end extending to the lower part of the storage tank and open to the liquid therein and the other end of the conduit communicating with said indicating device, an automatically operated. pump having an outlet communicating with the conduit and an air inlet opening above the liquid in the tank, said pump having an oscillatory member operable by the surge of the liquid in the tank, the pump being operated by said member for producing and maintaining fluid pressure in said conduit.

ing communication between said discharge 22. A liquid level gauge for indicating the height of the liquid in a storage tank intended to be subjected to movement, compris an indicating device responsive to iiuid p sure, conduit having one end enlarged to form a chamber and extending to the lower part of the storage tank with vents opening the lower end of the chamber to the liq in the tank and the other end of the conduit communicating with said indicating device, an automatically operated pump having an outlet communicating with the conduit and an air inlet opening above the liquid in the tank, said pump having means operable by the sur e of the liquid in the tank, the pump being operated by said means for producing and maintaining fluid pressure in said conduit.

23. The combination of a tank for storing liquid intended to be subjected to movement a pressure responsive liquid level gauge, a chamber open at its lower end to the interior of the lowestpart of the tank, a tube leading from chamber to the gauge, said tube and chamber forming a closed conduit between the interior of the tank and the gauge, an air pump mounted in fixed relation to the tank having an outlet communicating with the conduit and an inlet opening to the at mosphere, and operating means for the pump having a pivoted element operatively con nected with the pump, said. element being oscillative in the tank due to movement of the latter to operate the pump to force air into the conduit to maintain therein an air column to transmit the liquid pressure in the tank to the gauge.

24. The combination of a tank for storing liquid intended to be subjected to movement and a pressure responsive liquid level gauge, with means including an equalizing chamber providing a closed conduit between the interior of the lowest part of the tank and the gauge, an air pump fixedly mounted in the tank having an outlet communicating with the conduit, and an inlet opening to the at mosphere, said pump adapted to maintain an air column in the conduit between the tank and gauge to transmit the liquid pres sure in the tank to the gauge, and a vane pivoted within the tank and connecteu with the movable pump member, said vane being responsive to the surging imparted to the contained liquid by its movement in the tank, the movement of the vane operating the movable pump member.

25. A liquid level gauge for indicating the height of the liquid level in a storage tank intended to be subjected to movement, comprising an indicating device responsive to fluid pressure, a conduit having one end extending to the lower part of the storage tank and open to the liquid therein and the other end of the conduit communicating with said indicating device, a fluid pump having an inlet opening communicating with the atmosphere and an outlet opening, a pipe lead ing from said last-mentioned opening to communication with said conduit, and valve means controlling the passage of said fluid through said pipe, said pump having an actuating member responsive to the surge of the liquid in the tank, the pump being operated by said member for producing and maintaining fluid pressure in said conduit.

A liquid level gauge for indicating the height of the liquid level in a storage tank intended to be subjected to movement, comprising an indicating device responsive to fluid pressure, a conduit having one end extending to the lower part of the storage tank and open to the liquid therein and the other end of the conduit communicating with said indicating device, a pump having a restricted outlet opening communicating with the conduit and a restricted opening opening above the liquid, said pump having an actuating member responsive to the surge of the liquid in the tank, the pump being operated by said member for producing and maintaining fluid pressure in said conduit.

27. A liquid level gauge for indicating the height of the liquid level in a storage tank intended to be subjected to movement, comprising an indicating device responsive to fluid pressure, a conduit having one end on tending to the lower part of the storage tank and open to the liquid therein and the other end of the conduit communicating with said indicating device, a pump having a restricted outlet opening communicating with the conduit and a restricted opening opening above the liquid, said pump having an actuating member responsive to the bodily movement of the tank, the pump being operated by said member for producing and maintaining fluid pressure in said conduit.

28. A liquid level gauge for indicating the height of the liquid level in a storage tank, comprising an indicatin device responsive to fluid pressure, and conduit having one end extending to the lower oart of the storage tank and open to the liquid therein and the other end of the conduit communicating with said indicating device, a pump hav ing restricted outlet means communicating with the conduit and a restricted inlet means above the liquid, said pump having an actuated member responsive to the bodily movement of the pump for producing and maintaining fluid pressure in said conduit.

In testimony whereof, I have signed my name to this specification.

JAMES MACGALLUM, JR. 

